The present invention relates to a pneumatic tire, more particularly to a tread pattern capable of significantly improving the traction/braking performance and lateral grip performance during running off the road.
Usually, off-road sport tires used in rally, dirt trial and the like are provided with block-type tread patterns in order to obtain superior road grip performance such as traction/braking performance and lateral grip performance.
In the European patent application publication No. EP1992503A1, a pneumatic tire is provided with an asymmetrical tread pattern in order to improve the traction performance and lateral grip performance, wherein the outside part of the tread portion to be placed on the outside of a vehicle is provided with: a plurality of oblique grooves extending from the outside tread edge to the tire equator while inclining to the intended rotational direction, and a plurality of connecting grooves extending between the oblique grooves while inclining to the same direction as the oblique grooves. On the other hand, the inside part of the tread portion to be placed on the inside of the vehicle is provided with circumferential grooves and axial grooves which extends generally in the tire circumferential direction and axial direction, respectively.
By such groove arrangement, the traction performance and lateral grip performance are improved, but it was found that there is room for improvement in the lateral grip performance and traction/braking performance.